Effect of hypothermic perfusion on phacoemulsification in eyes with hard nuclear cataract: randomized trial

Abstract

To evaluate the effectiveness and safety of hypothermic perfusion in the phacoemulsification of hard nuclear cataract. Tertiary opthalmology center, China. Laboratory study and prospective randomized clinical trial. Rabbits and patients with hard nuclear cataract underwent phacoemulsification with perfusion temperatures at 4°C or 24°C. Anterior segment optical coherence tomography (AS-OCT), corneal endothelial cell count (ECC), and cornea sections were observed before the rabbits' operation and 1day and 7days postoperatively. AS-OCT, corneal ECC, and anterior chamber (AC) inflammation were observed before the patients' operation and 1day, 7days, and 30days postoperatively. The study comprised 40 rabbits and 80 patients. In the animal models, the mean central corneal thickness (CCT) in the 4°C group (370.4μm±45.5 [SD]) was thinner than in the 24°C group (496.7±121.5μm) 1day postoperatively (P<.001). The mean AC inflammation reaction grade in the 4°C group (1.1±0.9) was lower than in the 24°C group (2.2±0.8) (P=.0333). In clinical trials, the mean CCT and incisional corneal thicknesses in the 4°C group (600.7±51.8μm and 859.2±177.8μm, respectively) were thinner than in the 24°C group (655.3±85.0μm and 955.9±196.7μm, respectively) (P<.001). The endothelial cell density (P=.036) and hexagonality (P=.001) were higher in the 4°C group. The mean AC inflammation reaction grade in the 4°C group (0.6±0.6) was lower than in the 24°C group (1.3±1.0) 1day postoperatively (P=.004). Hypothermic perfusion in phacoemulsification of hard nuclear cataract is safe and it can effectively protect corneal endothelium, decrease corneal edema, and reduce AC inflammation in the early postoperative stage.